Extradition — Double criminality — Requirement that conduct constitute an offence under laws of both the requesting and the requested State — Extent of requirement — Whether necessary that offence be described in similar terms in both States — Extradition requested for charges of mass murder under legislation relating to war crimes and crimes against humanity — Whether mass murder a different crime from murder

Extradition — Jurisdiction of requesting State — Crimes allegedly committed outside territory of requesting State — War crimes and crimes against humanity — Whether crimes of universal jurisdiction

Extradition — Procedure — Evidence — Admissibility — Appeals — Role of Court of Appeals in reviewing decision of United States District Court in extradition proceedings — Role of courts and Executive in extradition

Extradition — Speciality — Requirement that requesting State refrain from prosecuting defendant for crimes other than those for which extradition granted — Extent of requirement — Whether dictating particulars of crime for which defendant might be charged — Nature of principle of speciality — Whether right to insist upon speciality belongs to requested State or to defendant

Jurisdiction — Universal — Crimes against international law — War crimes and crimes against humanity — Jurisdiction of municipal courts — Courts of State which did not exist at time offences committed

Relationship of international law and municipal law — Customary international law — Whether part of United States law

War and armed conflict — Enforcement of the laws of war — War crimes and crimes against humanity — Definition — Jurisdiction over — The law of the United States